Examining the impact of non-neutral sitting postures on vibration transmissibility up the spine

移动机械的操作员暴露在全身振动中。现有的国际标准建议振动暴露的安全暴露持续时间；然而，现有标准没有考虑到与非中性工作姿势相关的伤害风险增加。然而，许多机器操作员必须采用向前弯曲和扭曲的颈部和躯干姿势来操作移动机械。为了了解非中性姿势对受伤风险的影响，结合全身振动暴露，可以研究振动通过身体的传递。该项目将测量在不同水平的振动暴露和旋转躯干/颈部姿势下从座椅到脊柱和头部几个层次的振动传递率。如果振动在身体中的传播方式不同，这可能表明在非中性姿势下工作的机器操作员比暴露在相同振动下的中性姿势下的操作员有更高的受伤风险。对非中性状态下振动传递性的更好理解也可用于改进用于确定安全振动暴露持续时间的现有国际标准。标准的提高将有助于保护设备操作员免受负面健康后果的影响，如腰痛。防止受伤将有利于机器操作员、工业和加拿大经济。

Operators of mobile machinery are exposed to whole-body vibration. International standards exist to suggest safe exposure durations for vibration exposure; however, the existing standards do not account for increased injury risk associated with non-neutral working postures. Yet, many machine operators have to adopt bent forward and twisted neck and trunk postures in order to operate mobile machinery. In order to understand the impact of non-neutral postures, in combination with whole-body vibration exposures, on injury risk, the transmission of vibration through the body can be studied. This project will measure vibration transmissibility from the seat to several levels of the spine and head under different levels of vibration exposure and rotated trunk/neck postures. If vibration travels through the body differently it could indicate machine operators working in non-neutral postures have a higher injury risk than operators in neutral postures exposed to the same vibration. An improved understanding of vibration transmissibility under non-neutral postures can also be used to improve existing international standards that are used to determine safe vibration exposure durations. Improved standards will help to protect equipment operators from negative health outcomes, such as low-back pain. Injury prevention will be beneficial to machine operators, industry and the Canadian economy.